"Could be due to TfL telling everyone to avoid that station at the moment due to the escalator works."

A ha! Of course.... Yes. That would make a lot of sense.

A bit silly really - because the effect of the London-wide lies TfL are spreading about Bank/Monument is that the demographics of the users of the station will have changed markedly: far more Londoners (tourists will have been scared off) --- and fewer people overall, meaning each person gets more chance to see the posters.

A good salesperson would be able to get an *increased* rate for those spots during these works!